Weight loss associated with low-energy diets with different glycaemic loads does not improve arterial stiffness: a randomised clinical trial

We evaluated the effects of two low-energy diets with different glycaemic loads on arterial stiffness in adults with excess weight. This was a 45-day parallel-group, randomised clinical trial including seventy-five participants (20-59 years; BMI 32 kg/m(2)). They were assigned to two similar low-energy diets (reduction of similar to 750 kcal.d(-1)) with macronutrient composition (55 % carbohydrates, 20 % proteins and 25 % lipids) but different glycaemic loads: high-glycaemic load (HGL 171 g.d(-1); n 36) or low-glycaemic load (LGL 67 g.d(-1); n 39). We evaluated: arterial stiffness (pulse wave velocity, PWV); augmentation index (AIx@75); reflection coefficient; fasting blood glucose; fasting lipid profile; blood pressure and body composition. We found no improvements in PWV (P = 0 center dot 690) and AIx@75 (P = 0 center dot 083) in both diet groups, but there was a decrease in the reflection coefficient in the LGL group (P = 0 center dot 003) compared with baseline. The LGL diet group showed reductions in body weight (Delta -4 center dot 9 kg; P = 0 center dot 001), BMI (Delta -1 center dot 6 kg/m(2); P = 0 center dot 001), waist circumference (Delta -3 center dot 1 cm; P = 0 center dot 001), body fat (Delta -1 center dot 8 %; P = 0 center dot 034), as well as TAG (Delta -14 center dot 7 mg/dl; P = 0 center dot 016) and VLDL (Delta -2 center dot 8 mg/dl; P = 0 center dot 020). The HGL diet group showed a reduction in total cholesterol (Delta -14 center dot 6 mg/dl; P = 0 center dot 001), LDL (Delta -9 center dot 3 mg/dl; P = 0 center dot 029) but a reduction in HDL (Delta -3 center dot 7 mg/dl; P = 0 center dot 002). In conclusion, a 45-day intervention with low-energy HGL or LGL diets in adults with excess weight was not effective to improve arterial stiffness. However, the LGL diet intervention was associated with a reduction of reflection coefficient and improvements in body composition, TAG and VLDL levels.